Elizabeth Salvo
McMaster University, Canada
Title: Towards practical bacterial biosensor assays for on-site applications
Biography
Biography: Elizabeth Salvo
Abstract
Air drying in the natural polymers pullulan and acacia gum has been reported previously as an effective bacterial preservation strategy. The use of this method for the preservation of sensing bacteria is presented here. Colorimetric Escherichia coli bioreporters for tetracycline and arsenate analytes has retained responsivity following air-drying in pullulan sugar. Additionally, the method was used to immobilize sensing cells onto paper substrates, and a screen of various materials was conducted to determine the optimal composition of a drying matrix for responsivity. The viscosity enhancer pullulan, acacia gum, polyvinylpyrrolidine and gelatin were paired with osmoprotectants in some standard bacterial culture mediums. The air-drying process is simpler, less expensive, requires less sophisticated instrumentation, and leads to much higher bacterial survival rates compared to the gold standard method for bacterial preservation, lyophilization. Simplicity of the method paired with applicability to simple platforms such as paper test strips makes this research an important step toward the usage of sensing microbes for the detection of a variety of biologically relevant analytes in the field.